The present invention relates to apparatus for protecting against the hazards of smoke and other noxious gases.
Fires, chemical spills, toxic fumes, and odors are an ever present danger to the occupants of buildings, factories, mines, or the like, especially when an escape route or exit from the location is not readily available. Various portable devices have been devised to assist an occupant of such an area to escape.
Examples of such prior air survival units are illustrated in U.S. Pat. Nos. 4,502,157; 4,554,683; 3,562,813; and 966,739. U.S. Pat. No. 4,502,157 is broadly directed to a protective enclosure which essentially is pulled taut against the chest of the wearer and secured in this particular position by any fastening means, such that the body of the wearer including, in particular, the wearer's own chest, serves to close the open end of the bag. In short, U.S. Pat. No. 4,502,157 relates to a particular way of draping and supporting a protective enclosure on the user.
U.S. Pat. No. 4,554,683 complements the coverage of U.S. Pat. No. 4,502,157 that it broadly covers a protective enclosure which is designed to have its open end secured about the waist of the wearer and which includes armports through which the wearer inserts his or her arms.
U.S. Pat. No. 3,562,813, which expired on Feb. 16, 1988 describes a protective head enclosure which is essentially a rigid structure and includes cylindrical lower section, an intermediate transparent or window section and an upper hemispherical section.
The expired U.S. Pat. No. 996,739 discloses a protective enclosure which obviously was fabricated from the catagories of materials available in the early 1900's rather than modern day plastics. In all events, the hood or head piece is of an extent such that it drapes against the chest and the back of the wearer and is provided with eye openings which are covered by transparent material.
An objective of the present invention is to provide an improved air survival unit that is compact, inexpensive, and lightweight and which enables the user to breathe normally in a toxic environment for a sufficient period of time to escape therefrom.
Another objective is to provide such an improved survival unit in which the hood is formed of a flame-resistant, transparent plastic film which provides face and eye protection without effective visibility for the user and which provides free mobility to the user because no hookups or connections to sources outside the hood are required. Likewise, no physical obstructions or protrusions violate the integrity of the hood.
Still another objective of the invention is to elimiate the need for an oxygen generator or canister which is inherently unsafe in a fire situation because of the danger of explosion.
A further objective of the invention is to provide such a survival unit in which the length of breathing time provided by the unit may be increased by increasing the size of the hood to accommodate a larger reservoir of air.
A particular objective of the present invention is to provide a protective enclosure particularly designed for use in overcoming the great danger of smoke eminating from a fire in the lower elevation of tall buildings, billowing up to the upper rooms, and choking out the supply breathable life supporting air.
The objects and various other advantages will be seen from the following disclosure of the present invention.